// Copyright (c) 2017-2023 Broadcom. All Rights Reserved. The term "Broadcom" refers to Broadcom
// Inc. and/or its subsidiaries.
//
// This software, the RabbitMQ Java client library, is triple-licensed under the
// Mozilla Public License 2.0 ("MPL"), the GNU General Public License version 2
// ("GPL") and the Apache License version 2 ("ASL"). For the MPL, please see
// LICENSE-MPL-RabbitMQ. For the GPL, please see LICENSE-GPL2.  For the ASL,
// please see LICENSE-APACHE2.
//
// This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND,
// either express or implied. See the LICENSE file for specific language governing
// rights and limitations of this software.
//
// If you have any questions regarding licensing, please contact us at
// info@rabbitmq.com.
package com.rabbitmq.perf;

import java.io.*;
import java.util.ArrayList;
import java.util.List;

/** */
public class LocalFilesMessageBodySource implements MessageBodySource {

  private final long ZERO = 0L;

  private final List<byte[]> bodies;

  private final String contentType;

  public LocalFilesMessageBodySource(List<String> filesNames, String contentType)
      throws IOException {
    bodies = new ArrayList<>(filesNames.size());
    for (String fileName : filesNames) {
      File file = new File(fileName.trim());
      if (!file.exists() || file.isDirectory()) {
        throw new IllegalArgumentException(fileName + " isn't a valid body file.");
      }
      try (BufferedInputStream inputStream = new BufferedInputStream(new FileInputStream(file))) {
        byte[] body = new byte[(int) file.length()];
        inputStream.read(body, 0, body.length);
        bodies.add(body);
      }
    }
    this.contentType = contentType;
  }

  public LocalFilesMessageBodySource(List<String> filesNames) throws IOException {
    this(filesNames, null);
  }

  @Override
  public MessageEnvelope create(int sequenceNumber) {
    return new MessageEnvelope(bodies.get(sequenceNumber % bodies.size()), contentType, ZERO);
  }
}
